A growing number of scholars have begun to fill in the gap, however, working in an unconventional academic specialty they call new religious movements. This emerging field has not only attracted traditional religion experts but also psychologists, anthropologists and literary critics. It has even brought forth a separate study group within the American Academy of
Religion called the New Religious Movements Group, for scholars interested in the topic.
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It is ''a growth industry in the academy,'' said Phillip C. Lucas, an associate professor of religious studies at Stetson University in De Land, Fla.
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Although new faiths are often summarily dismissed, yesterday's new religion may be today's powerhouse. Consider the Church of Jesus Christ of Latter-day Saints, the Mormons, which began with a handful of people in an upstate New York village in 1830 and now counts more than 10 million members worldwide.

William Ashcraft, a professor of religious studies at Truman State University in Kirksville, Mo., said that most new-faith adherents see themselves as set apart from the surrounding culture. ''Scholars have come to think of these
groups as anybody who is alternative to the mainstream,'' he said. (...)

Like most experts, however, they don't use the word cult. ''Practically every religion we know of is labeled a cult in some country,'' Ms. Brasher said.
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More recently, the cultural upheavals of the 1960's helped diminish the social taboos against religious experimentation. As Mr. Lucas explained, ''There is far less stigma attached to searching outside the mainstream when it comes to one's own religion.'' And today, new technologies are once again causing upheavals in American life. ''I do think it's easier to be involved in a new religious movement now because of the Internet,'' Ms. Brasher said. ''Geography is no longer destiny. It's easier for small religious groups to form. They've got a medium through which they can encourage each other.''

Although experts point out that new religions vary widely, they do concede that those bitterly hostile to society have a potential for violence, like Aum Shinrikyo, the Japanese group that used poison gas in the Tokyo subway, or Jim Jones's People's Temple, which engaged in a mass suicide in the jungles of Guyana. They argue that a better understanding of these groups' beliefs may help government agencies deal peacefully with them, avoiding encounters that can lead to loss of life.

But containing violence isn't the only motive for the fascination with new religious movements. Many scholars argue that these groups are often the purveyors of more widely accepted ideas.

''In the alternative religions of today,'' Ms. Brasher said, ''could be our habits and cultures of tomorrow. Some of those are very exciting and some of those are quite scary.''